Impact of one-day fasting, ketogenic diet or exogenous ketones on control of energy balance in healthy participants

Franziska A Hägele; Rebecca Dörner; Jana Koop; Marie Lübken; Ulrike Seidel; Gerald Rimbach; Manfred J Müller; Anja Bosy-Westphal

doi:10.1016/j.clnesp.2023.03.025

Impact of one-day fasting, ketogenic diet or exogenous ketones on control of energy balance in healthy participants

Clin Nutr ESPEN. 2023 Jun:55:292-299. doi: 10.1016/j.clnesp.2023.03.025. Epub 2023 Apr 10.

Authors

Franziska A Hägele¹, Rebecca Dörner¹, Jana Koop¹, Marie Lübken¹, Ulrike Seidel², Gerald Rimbach², Manfred J Müller¹, Anja Bosy-Westphal³

Affiliations

¹ Department of Human Nutrition, Institute of Human Nutrition and Food Sciences, Kiel University, Düsternbrooker Weg 17, 24105 Kiel, Germany.
² Department of Food Sciences, Institute of Human Nutrition and Food Sciences, Kiel University, Hermann-Rodewald-Strasse 6, 24098 Kiel, Germany.
³ Department of Human Nutrition, Institute of Human Nutrition and Food Sciences, Kiel University, Düsternbrooker Weg 17, 24105 Kiel, Germany. Electronic address: abosyw@nutrition.uni-kiel.de.

PMID: 37202059
DOI: 10.1016/j.clnesp.2023.03.025

Abstract

Background & aims: Oral ketone supplements may mimic the beneficial effects of endogenous ketones on energy metabolism as β-hydroxybutyrate has been proposed to increase energy expenditure and improve body weight regulation. Therefore, our objective was to compare the effects of a one-day isocaloric ketogenic diet, fasting and supplementation with ketone salts on energy expenditure and appetite perception.

Methods: Eight healthy young adults (4 women, 4 men, age 24 ± 3 years, BMI 24.3 ± 3.1 kg/m²) participated in a randomized cross-over trial with four 24 h-interventions in a whole room indirect calorimeter at a physical activity level of 1.65: (i) total fasting (FAST), (ii) isocaloric ketogenic diet (3.1% energy from carbohydrates (CHO), KETO), (iii) isocaloric control diet (47.4% energy from CHO, ISO), and (iv) ISO supplemented with 38.7 g/d ketone salts (exogenous ketones, EXO). Effects on serum ketone levels (15 h-iAUC), energy metabolism (total energy expenditure, TEE; sleeping energy expenditure, SEE; macronutrient oxidation) and subjective appetite were measured.

Results: Compared to ISO, ketone levels were considerably higher with FAST and KETO and little higher with EXO (all p > 0.05). Total and sleeping energy expenditure did not differ between ISO, FAST and EXO whereas KETO increased TEE (+110 ± 54 kcal/d vs. ISO, p < 0.05) and SEE (+201 ± 90 kcal/d vs. ISO, p < 0.05). CHO oxidation was slightly decreased with EXO compared to ISO (-48 ± 27 g/d, p < 0.05) resulting in a positive CHO balance (p < 0.05). No differences between the interventions were found for subjective appetite ratings (all p > 0.05).

Conclusion: A 24 h-ketogenic diet may contribute to maintain a neutral energy balance by increasing energy expenditure. Exogenous ketones in addition to an isocaloric diet did not improve regulation of energy balance.

Clinical trial registration: NCT04490226 https://clinicaltrials.gov/.

Keywords: Appetite control; Energy balance; Energy expenditure; Ketogenic diet.

Publication types

Randomized Controlled Trial

MeSH terms

Adult
Diet, Ketogenic*
Energy Metabolism / physiology
Fasting
Female
Healthy Volunteers
Humans
Ketones
Male
Salts
Young Adult

Substances

Ketones
Salts

Associated data

ClinicalTrials.gov/NCT04490226